PH7 is an in-process software library that implements a highly-efficient embeddable bytecode compiler and a virtual machine for the PHP programming language. It implements most PHP 5.3 constructs, including heredoc, nowdoc, gotos, classes, anonymous functions, and closures, along with powerful extensions such as function overloading, comma expressions, full type hinting, string comparison operators, and more. It is the ideal library for enhancing your application or device (such as router or set-top box) with dynamic Web interfaces, with the benefits and power of PHP and without the overhead incurred by process creation. As an embedded interpreter, it allows multiple interpreter states to coexist in the same program, without any interference between them.

HGL is a compiler/interpreter suite for developing images. It features its own simple but powerful language, Lua integration, output in various formats as well as runtime input handled by plugins, and easy integration into various environments like Web servers or graphical applications. The input is taken from a source file, which has to be compiled for quick and frequent access by the interpreter. An interpreter then runs the compiled files, takes input from custom plugins (if neccessary), and outputs its result via custom plugins.

pyC11 is a grammar to parse programs in the C programming language following ISO/IEC 9899:2011. It is written using pyPEG, a parsing framework for Python. The grammar supports Python 2.7 and 3.x. The test bench requires py.test.

Pascal-P4 for Free Pascal and Delphi is a port of a Pascal compiler written at ETH Zurich in 1976. The source code of the compiler is documented in the book "Pascal Implementation" by Steven Pemberton and Martin Daniels. The purpose of this project is to make Pascal-P compilable by Free Pascal and Delphi while keeping the changes to a minimum and preserving the line numbering as much as possible.

javacx is a Java compilation tool which allows all the sources files which the Java standard compiler task finds to be preprocessed by multiple commands. Note that it uses your existing javac compiler, so will work as you update your system.

Scheme Art is a portable scheme compiler written in C++ that uses adaptive systems (chaos theory) and AI libraries for compiling and interpreting (at runtime.) It was originally devised as a Web REPL implemented in PHP code.

Bircc (Bircc Is a Reusable C Compiler) is a reusable, portable C compiler written in C. It supports easy cross-compiling and is easy to extend and reuse. It has decent performance, though this is secondary to all-around ease of use.